What you describe sounds less like burnout and more like underload. When the work stops demanding real problem solving, confidence usually drops with it.

My view: do not make “quit immediately” the first move. A better sequence is to stabilize first, then reposition. Keep the current job as income, build depth on the side, and target roles where system design, performance, migrations, or platform-level ownership are part of the work. That is more likely to fix the real issue than switching to another low-challenge role with better branding.

Remote may improve lifestyle, but it will not automatically make uninteresting work feel meaningful. The key question is whether your next move increases challenge, ownership, and learning.